CLI improvements

[jmelburg]

@jmelburg , is this something you can try to look at? The use case here is that it would be great if we could simply run uvx pdstools which would ensure you have python and the app dependencies installed, and run the health check or decision analyzer app. We could default to health check, give the user an option, or think of something else. I tried a first stab in this PR but I never got to completing it.

Originally posted by @StijnKas in #395 (comment)